Decrease font size
Increase font size
Topic Title: Has anybody encountered a special facility?
Topic Summary:
Created On: 17 December 2013 08:35 AM
Status: Read Only
Linear : Threading : Single : Branch
Search Topic Search Topic
Topic Tools Topic Tools
View similar topics View similar topics
View topic in raw text format. Print this topic.
 17 December 2013 08:35 AM
User is offline View Users Profile Print this message


Posts: 608
Joined: 06 May 2007

In Spy Catcher Peter Wright mentions an electronic device deployed by MI5 called a special facility that was installed in a telephone to enable it to transmit sounds in the room whilst on-hook. One was used in the Egyptian embassy in London to enable MI5 officers listen to the number of clicks on the code setting wheels of cipher machine which resulted in MI5 breaking the code and deciphering top secret communications between the embassy and the government in Egypt.

Has anybody ever encountered a special facility? I find it unlikely that MI5 would have recovered ever single special facility they installed because of the risk involved and the economics of manpower. Knowledge of them was (and still officially is) classified information so Post Office Telephone technicians would not have removed them on request because they wouldn't have known they existed. Therefore it is possible that some special facilities have found their way into the hands of the general public.

Messrs Furber and Sobrany, who ran a business supplying telephone equipment in the early 1990s, encountered a 706 telephone with a strange modification not described anywhere in the N-diagrams. Initially it was thought to be for EMI suppression but experiments revealed that it transmitted sounds in the room down the telephone line whilst on hook although an amplifier was required to listen to them. They publicised their findings on a few dial-up bulletin boards back then and later on the internet until the pages were removed from the website in 1999 due to suspected harassment and stalking. The web pages about the modification were kindly supplied to my son a few years ago (on a condition of trust) which allowed him to replicate it but he is inconclusive that it actually was a special facility installed by MI5.
 08 January 2014 10:42 PM
User is offline View Users Profile Print this message


Posts: 3532
Joined: 31 March 2005

Even in the 80's and 90's there were 'secret' jumper blocks in telephone exchanges. If they wanted to eves drop on your call, someone would just duplicate your jumper from your line to the block and no one would even know- and it was never recorded anywhere.

When 3G mobile networks were designed, it allowed for remote over ride of several features. For instance someone could call you and be heard on speakerphone even though you never answered the call in the first place. It would'nt be a leap of programming to turn cameras and mics on remotely.
To my knowledge its never actually been done on a phone, well not that anyone would admit to anyway.

Lack of planning on your part doesn't make it an emergency on mine....

Every man has to know his limitations- Dirty Harry
 12 January 2014 08:40 AM
User is offline View Users Profile Print this message


Posts: 608
Joined: 06 May 2007

Strowger telephone exchanges were fitted with subscriber's interception circuits that are described in Telephony by Atkinson. They were officially intended for monitoring the quality of sound on telephone calls but ended up being used for surveillance of suspects. Spy Catcher describes this telephone tapping process in detail and how it was carried out by the Post Office Special Investigations Unit because it was illegal for MI5 to monitor a live Post Office telephone line directly. Intercepted calls were recorded, initially on dictaphone cylinders, then transcribed.

The special facility was not a telephone tapping device because it worked when the phone was on-hook. Therefore it was (in theory) exempt from the protocols of telephone tapping, which meant that MI5 could collect intelligence obtained from them directly without any involvement from the Post Office Special Investigations Unit.

See Also:

FuseTalk Standard Edition v3.2 - © 1999-2016 FuseTalk Inc. All rights reserved.